I was experimenting with some long exposures, up to one and a half minutes. It takes a full minute before the camera will return to use and allow you to view the image, and I can't understand why. The file size is no larger, so why does it take so long.

On long exposures under 30 seconds, the camera will return to use immediately, but go past 30s and you run into those long delays before the camera will come back into action. With a 35 second exposure, it takes about 10 seconds before the camera will come back on.